HVAC monitoring addendum to scope of work, August 2002

NYC 9/11 Public Portal Document

23 * Central ventilation systems (cont)

Dust/DirtZDebris Suspect WTC-Related Dust Estimate % of total dust loading System Light Heavy Component (<1/16 inch 1/16 inch Present? System Components Substrate Material None depth) depth (Y/N) Outside air intake louvers, grates and/or screens Outside air duct Outside air damper(s) Return air grilles Return air plenum Return air plenum damper Return air ducts Turning vanes Mixing chambers Filter rack(s) Filter banks/media Pre-heat coils Cooling coils Re-heat coils Humidification and/or air cleaning equipment Fire dampers In-line re-heat coils Acoustical blower housing lining Duct connectors Blower assembly including blower wheel, blower housing, air vanes, in­ line noise attenuators, acoustical treatments (e.g. baffles, duct linings) Condensate drain pan Condensate accumulator Supply air plenum Supply air plenum damper(s) Supply air ducts -High pressure - main trunk -Low pressure - branches Supply plenum or supply duct linings Supply air duct damper(s) Supply air diffusers Terminal boxes Open or ducted passive ventilation shaft(s) Other Information: n Unit cycled prior to inspection □ Color of Dust/Dirt/Debris

s □ Filter loading (general ression) n Water damage Filter bypass (describe) Abraded/delaminated acoustical lining H Visible stispect mold growth___________________ Evidence of animal incursion (carcasses, feathers, fecal matter)

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